Validation of a new test for insulin sensitivity

Insulin resistance is a major risk factor for type 2 diabetes and heart disease. Currently the most accurate methods for measuring insulin sensitivity are the 'gold-standard' euglycaemic clamp and the intravenous glucose tolerance test, which are complicated and expensive and can only be used in small research trials. For larger population-based studies crude surrogates are available to measure insulin sensitivity (most are based on fasting insulin and glucose).

We propose a new, dynamic, 30-minute test developed from our clinical model-based glucose and insulin control trials. This model's clinical accuracy is vastly superior to those described previously and has been compared (under simulated conditions) with 146 euglycaemic clamp tests, where it has performed remarkably well.

Novel test challenges the gold standard

We are currently validating this novel test against the gold standard euglycaemic clamp test in a new population. If this test proves to be easy to perform and relatively inexpensive and reliable, it could be used in large research studies of individuals at high risk of diabetes and cardiovascular disease. We believe the proposed test could potentially be used in clinical practice and would be of major international importance given the increasing numbers of individuals at risk of diabetes and heart disease.

This project is a collaboration with winners of the 2006 Health Innovation Awards Supreme Award:

Recent results may enable new clinical applications

Our 2011 publication's results show accurate insulin sensitivity (SI) estimation is possible in the absence of insulin or C-peptide assays using the proposed method. Such estimates may only need to be generated once and then used repeatedly in the future for isolated cohorts. The reduced correlation using the second cohort in this study was due to this cohort's bias towards low SI insulin resistant subjects, limiting the data set's ability to generalise over a wider range.

All the correlations remain high enough for the DISTq to be a useful test for a number of clinical applications. The unique real-time results can be generated within minutes of testing as no insulin and C-peptide assays are required and may enable new clinical applications.